I beam strength formula

[allerellie]

Is there a simple formula to find out how much uniform weight an I beam can support. example type in the size of the beam (W8)and the span (24ft)and come up with the lbs it can support (if supported on the ends).

 

[whyun]

Considering only flexural stress of the steel beam, you can derive an equation for uniform load w from these equations:

M = Fb S
M = w L^2 / 8

solving for w,

w = 8 Fb S / L^2
where Fb is the allowable bending stress

There isn't one single simple formula for obtaining the maximum uniform load a beam can support as it depends on the support conditions. In addition, flexural stress may not be the controlling factor since for long spans, beam deflection usually controls.

Invest in a relatively inexpensive steel beam program called RAMSBeam from

http://www.ramint.com/products/r_sbeam.jsp

 

[UcfSE]

You should be looking for a professional. There are more things to do than simply sticking numbers in an equation. You have to know which numbers, where they go, and which equations to check.

 

[jike]

I second what UcfSE stated. There are many considerations beyond just bending stress level for instance acceptable deflection, lateral bracing, shear, connections, etc.

 

[denoid]

I agree with UcfSE and jike. Deflection would be a huge concern for me with a W8 spanning 24 feet, even if braced and properly connected.